diff --git a/internal/openapi/schema.go b/internal/openapi/schema.go
index b28b609..e2d4a56 100644
--- a/internal/openapi/schema.go
+++ b/internal/openapi/schema.go
@@ -354,14 +354,17 @@ func describeBody(op *operationInfo, field string, maxDepth int, names SchemaFla
 	for _, p := range op.PathParams {
 		doc.Args = append(doc.Args, SchemaArg{
 			Name:        p.Name,
-			Placeholder: "<" + slugify(p.Name) + ">",
+			Placeholder: "<" + canonicalName(p.Name) + ">",
 			Type:        p.Type,
 			Description: p.Description,
 		})
 	}
-	for _, q := range op.QueryParams {
+	// Use the same resolution as flag registration so collision renames
+	// (--param-base-url, --foo-2) are reported exactly as the CLI accepts them.
+	for _, qf := range resolveQueryFlags(op) {
+		q := qf.Param
 		doc.QueryParams = append(doc.QueryParams, SchemaQueryParam{
-			Flag:        "--" + slugify(q.Name),
+			Flag:        "--" + qf.Name,
 			Name:        q.Name,
 			Type:        q.Type,
 			Enum:        q.Enum,
diff --git a/internal/openapi/schema_test.go b/internal/openapi/schema_test.go
index dcaef88..5e9a2a6 100644
--- a/internal/openapi/schema_test.go
+++ b/internal/openapi/schema_test.go
@@ -622,9 +622,14 @@ func TestSchema_BodylessGetDescribesArgsAndQueryParams(t *testing.T) {
 		t.Fatalf("args = %v, want 1 entry", doc.Args)
 	}
 	arg := doc.Args[0]
-	if arg.Name != "widgetId" || arg.Placeholder != "<widgetid>" || arg.Type != "string" || arg.Description != "Widget UUID" {
+	if arg.Name != "widgetId" || arg.Placeholder != "<widget-id>" || arg.Type != "string" || arg.Description != "Widget UUID" {
 		t.Errorf("arg = %+v, want the widgetId path param", arg)
 	}
+	// The placeholder and flag spellings must match what --help and the usage
+	// line print (canonicalName), not the older bare-lowercase slugify form.
+	if strings.Contains(arg.Placeholder, "widgetid") {
+		t.Errorf("placeholder %q uses the old slugify spelling; want kebab-case", arg.Placeholder)
+	}
 
 	byFlag := map[string]SchemaQueryParam{}
 	for _, q := range doc.QueryParams {
@@ -1132,3 +1137,55 @@ func TestSchema_StaticDepthLimitMatchesDescriber(t *testing.T) {
 		t.Errorf("static truncation = %s, describer truncation = %s", got, want)
 	}
 }
+
+// collidingQueryTestSpec has query params whose canonical flag names collide:
+// "baseUrl" with the global --base-url, and "branchId"/"branch_id" with each
+// other. Flag registration renames these (see resolveQueryFlags); --schema must
+// advertise the renamed flags, not the bare canonical spelling.
+const collidingQueryTestSpec = `{
+  "openapi": "3.1.0",
+  "info": {"title": "test", "version": "1.0"},
+  "paths": {
+    "/api/v1/widgets": {
+      "get": {
+        "operationId": "widgetsList",
+        "tags": ["widgets"],
+        "parameters": [
+          {"name": "baseUrl", "in": "query", "description": "Filter by URL", "schema": {"type": "string"}},
+          {"name": "branchId", "in": "query", "description": "Branch (camel)", "schema": {"type": "string"}},
+          {"name": "branch_id", "in": "query", "description": "Branch (snake)", "schema": {"type": "string"}}
+        ],
+        "responses": {"200": {"description": "ok"}}
+      }
+    }
+  }
+}`
+
+func TestSchema_QueryFlagsReflectCollisionRenames(t *testing.T) {
+	doc, err := runSchemaCmd(t, collidingQueryTestSpec, "list")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	got := map[string]string{}
+	for _, q := range doc.QueryParams {
+		got[q.Name] = q.Flag
+	}
+	want := map[string]string{
+		"baseUrl":   "--param-base-url",
+		"branchId":  "--branch-id",
+		"branch_id": "--branch-id-2",
+	}
+	for name, flag := range want {
+		if got[name] != flag {
+			t.Errorf("query param %q advertised as %q, want %q (the flag the CLI actually registers)", name, got[name], flag)
+		}
+	}
+
+	// And the advertised flags must all be accepted by the command itself.
+	cmd := subcommand(t, collidingQueryTestSpec, "list")
+	for _, flag := range want {
+		if cmd.Flags().Lookup(strings.TrimPrefix(flag, "--")) == nil {
+			t.Errorf("--schema advertises %s but the command does not register it", flag)
+		}
+	}
+}